Measuring whether organic matter is present or whether or not organisms are alive is an important part of biology and is key to the development of new drugs or of therapeutic technologies. In a MTT (tetrazolim-based colorimetric) detection method used for measuring apoptosis in biologic laboratories, hospitals, or pharmaceutical companies all over the world, samples may be simply, quickly, and objectively read using microplate reader equipment, and thus the method is extensively used as an apoptosis detection method. A method using XTT or MTS, which is a modified dye of MTT, is also used. In another method, the expression amount of apoptosis-related protein is obtained by separating and dissolving cells to separate proteins using a quantitative apoptosis analysis method for photographing an image formed after fluorescence dyeing to thus quantitatively analyze the absorbance of each cell based on the obtained image, and then by measuring a change in the relative expression amount of a specific protein using a specific protein inspection method (Western blot). A more convenient method is to measure OD600, which is mainly used to measure microbial death using an amount of spectral absorption in the 600 nm band.
The typical method for measuring apoptosis has the following drawbacks. A MTT analysis method is an inspection method for measuring the activity of intracellular mitochondria that reduces MTT tetrazolium, which is a yellow water-soluble substrate, into celadon water-insoluble MTT formazan (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide) based on the action of dehydrogenase. The MTT analysis method is widely used for tests for measuring apoptosis and the toxicity of various chemical substances. This technology is frequently used because reproducible optical density can be obtained using a minimum amount of physical treatment. However, when extracellular abiotic factors affect a process for reducing tetrazolium salts, a fatal error may occur in the analysis results. Accordingly, in apoptosis measurement, a costly dyeing reagent is used, and a lot of measurement time and labor are required. In addition, there are problems in that a region to be dyed may depend on a dyeing method and that it is not easy to perform quantification. Particularly, since it is not possible to observe the death process over time in a dyed sample, it is necessary to use an indirect method of manufacturing a plurality of samples and dying the different samples to measure the cell samples over time, rather than using the same sample. Particularly, flow cytometry (FACS) requires irreversible pretreatment, which involves sample labeling using a fluorescent reagent and detachment of adherent cells from the surface of a plate, followed by analysis. Therefore, when monitoring the growth and death processes of adherent cells, inevitable errors may occur to some degree. Finally, when the above-mentioned specific protein detection inspection method is used, there is a drawback in that many samples and experimental procedures must be prepared and performed.
An example of a conventional technology for measuring the state of living organism samples using a spectroscopic method includes Japanese Patent Publication No. 3712132 (entitled “Spectroscopic determination of properties of biological materials”). In this technology, contact with a specific activating agent is performed, and, with respect to the effect of the contact, only whether or not the cell function is improved is confirmed using infrared spectroscopic analysis. However, there is no confirmation of the change of the infrared spectrum associated with apoptosis therein.
In order to overcome the problems with the conventional measurement method and spectroscopic analysis method up to the hilt, the inventors of the present invention have developed an apparatus and a method for measuring whether organic matter is present or whether or not organisms (cells or tissue) are alive according to a simple process using the characteristic whereby an infrared absorption spectrum changes depending on whether organic matter is present or whether or not organisms are alive, thereby accomplishing the present invention.